1. Field of the Invention
The present invention pertains to a fastener, in particular to a pipeline fastener.
2. Description of the Related Art
An ordinary pipeline fastener is usually applied to fasten and connect two pipes. By means of the pipeline fastener, the two pipes can be communicated with each other, whereby the pipeline fastener is usually used in a hydraulic brake system of vehicles, such as a joint for connecting a brake fluid container with a brake fluid pipe. Consequently, the pipeline fastener is widely applied to varied fields.
Referring to FIG. 1 and FIG. 2, a conventional pipeline fastener 1 comprises a head 11, a shank 12 connected to the head 11, and a plurality of threads 13 spirally disposed on the shank 12. Wherein, a channel 122 is enclosed by an inner wall 121 defined inside the shank 12. One end of the channel 122 opposite to the head 11 is communicated with an outside. At least one hole 123 penetrating from an outer wall 124 of the shank 12 to the inner wall 121 thereof is formed on the shank 12 for facilitating the hole 123 to be communicated with the channel 122. The product is operated by fitting the shank 12 into a pipe a, connecting the channel 122 to an interior of the pipe a via the hole 123, and then fastening the threads 13 into another pipe b for allowing the channel 122 to be communicated with the pipe b. Whereby, the pipes a,b are jointed together through the pipeline fastener 1 for providing a fluid (not shown) to be sequentially conveyed from the pipe a, the hole 123, and the channel 122 to another pipe b.
Consulting FIG. 3, a production of the pipeline fastener 1 necessitates a punching procedure, that is to say, a hole is punched from the outer wall 124 of the shank 12 to the inner wall 121 thereof. During the punching procedure, burrs 2 are formed on a periphery of the hole 123, in other words, the burrs 2 which are not cleaned up are easily left on sections where the inner wall 121 and the outer wall 124 meet a surface 1231 of the hole 123 respectively. Generally, the burrs 2 are metal chips with high hardness and sharpness. If the burrs 2 fall and flow with the fluid in time of use, the pipes a,b or pumps are most probably damaged. To avoid the aforesaid drawback, a burr-cleaning procedure is necessary to be executed after the punching procedure of the pipeline fastener 1 is finished. The burrs 2 on the outer wall 124 can be removed with ease; however, processing works to remove the burrs 2 on the inner wall 121 are very complicated. In general, a cutting tool (not shown) is adopted to remove the burrs, which is operated by introducing the tool from the channel 122 into an inside of the shank 12 for cutting the burrs 2 at a convergence of the inner wall 121 and the surface 1231. Nevertheless, the above operation cannot remove the burrs 2 completely because the burrs 2 are not absolutely cut off and some of them still suspend on the inner wall 121 or are bent into the hole 123 while the cutting tool is inserted to contact to the burrs 2. Consequently, the conventional operation has a poor burr-removal effect. Moreover, some manufacturers adopt a method of using a high temperature generated while explosive substances explode and burn to melt the burrs 2 away for making sure the quality of the pipeline fastener 1. This aforesaid method has a preferable effect of removing the burrs but needs more processing procedures and requires much time and more production cost, which needs to be improved.